Minute ventilation (V̇E) can be increased by decreasing tidal volume.

About 1/3 of inhaled air reaches the conductive zone where it takes part in gas exchange.

About 1/3 of inhaled air reaches the respiratory zone where it takes part in gas exchange.

All inhaled air reaches the respiratory zone where it takes part in gas exchange.

Minute ventilation (V̇E) can be increased by increasing the respiratory rate.